The investigation found that author Jason Jung, a computer engineer at Yeungnam University in Korea, “was involved in submitting the fraudulent review reports” for four of the retracted papers, according to the publisher’s CEO. In the case of the other six, the authors didn’t appear to be involved.

Hindawi Publishing Corporation, which publishes over 400 journals, doesn’t ask authors for potential review suggestions — making a common route to fake peer review more difficult. In July, when Hindawi announced it was investigating the papers, it posted a statement saying that they suspected the editors had created fake reviewer accounts.

The retraction note on Jung’s papers — identical except for the title at the beginning — explains that each paper has